There may be a remote amplifier that isn't turning on. The fuse for it could be blown, but given the recent history it's more likely it's not getting the turn-on signal from the radio. Double-check the connectors, and be sure no pins have pushed out in them. The two smaller plugs with four wires each are the speaker wires. One larger plug might not be used, but check the wires in the other one. If you do that with the ignition switch turned on, it will be obvious if you have a bad connection and it starts working.